Driving gear unit



Sept- 9, 1947 R. E. THOMPSON E-r Al.

DRIVING GEAR UNIT Filed June 1l, 1945 Patented Sept. 9, 1947 UNITED "()LFFI'CEv 'DRIVING GEAR UNIT Roy E. Thompsom South Gate, anlolm- FK.

Moriis,Loslngelea Calif;

Application June 11, 1943i, Serial ida-490,532

(Cl. rlll-291) llai'm; 1v This invention relates to power transmission means-and particularly pertains vto `a driving gear unit,

In connection With airplane constructionI and operation certain types Vci installations Arequire that various individual units shall vloe controlled electrically and selectively operated at theunit, such 'for ,exampleV Yas bomb .door controls,` flap operating, and landing Vgear mechanism.. In` such devices it isfnecessarytof'install'.individual'motors :adjacent to theV point' of application of power, anelito interpose a pnvver` transmissiongear lunit between thev motor .and 'ther device to be operated, so `that ya desired. motive "force Willfbe createdzand applied;V Inl View :of theiact that -silchk structures are appliecl=lat various points upon` an airplane remote `irorn the controls, it 'is desirableto provide :brake mechanism acting automatically 'to interrupt the driving 'action when a predetermined resistance to 'driving force occurs. .It :is also esd sential. that such structures Vshall be light in `weight andvcompact in design. `tris thezaprincipal object of the present invention, therefore, to Lprovide a drivingv unitof 'the character described which is compact in design;V giving a :large gear reduction between the :driving motor 'and the driven element. and within vWhich is embodied a brake meclflanism,releasing under overload. icon.- ditions, the `saidunit `loeingxhousecl within an foil- `sealed case, Wlturebyvariations in` temperature and' altitudeV vWilltnot affect the lubrication.

It isfanother object of the` invention to 'provide a 'gear unit in whichv a planetary gearset and brake structure arey assembled in 'a manner to `permit unitary-assembly and `removal of various partsvvithout diiiiculty.

The present.inventionV contemplates theprovisionoi La `housing directly connected to an .elec- .tric motoror other prime Vmover structure, in which housing a removable gear imitandf` brake may he assembled, said gearv .unitincluding `a planetary Vgear fset; carried by the `driven shaft.

The invention is "illustraedrby way .of example in the. accompanying drawing in which the ligure isa lcentral'.longitudinal view through the driving unit indicating a fragmentary portion of the prime mover with which it is-assembled.

Reterringtmore particularly tothe drawing, -I D indicates a prime mover, here .shown asbengan electric motor.v The motor is tted with a bolting flange H- complementary to a -bolting ange l2 of a driving unit I3. The fbolting flange I2 is part of the :driving unit housi-ngjfdv and isseclired tothe motor bybolts l5. The motor is fittedvvith drive shaft I6 at the endfOf; which ageai: `l'l occurs. This gear is here shownfas a spun pinion in mesh with a gear wheel L81 The gear wheel lzis carried upon a shaft la'` which in `turn is 4supported by ball-bearing structures 2,0 and 2|. The outer raceway of the structure 2|] is mounted "Within a `cup 232 lfitted Within a `-bore Z3v of the housing. The Vdiameter -of the boreA 2-3A is` -suioient to permit *the-outer ra'cewayof-the-bearing t l1 to-pass `tlieretl'irough toan assembledposition.

'The gear wheel -18 is secured intermediate the two lbearings-byaPWoodruff fkey lfit1-carried. by vthe shaft 118. `At the end vof the-shaft adjacent to the :motor lill is a -nut "25 holding vthe shaft in place. At the `omiositefend of the shaft T9 is a lgearxpifnionZ. This pinion may -be `formediritegral with the sha-iter- -mountedl'thereon lInany event it is large enough to form a stop for fthe Vsection W; packing.-ring-`3t".seals the fboss 34 aroundfthe driven `shaft 3-2. The lower housing section. M1 @is riitted wit-ha fholtingilange 35u/bleh ,is counterboned and receives `'an extensionl 360i 'halting fiange .31 carried J.by Vthe upper .housing section t4. 'The'bolting flanges are. secured together by: bolts 33a IBy` this arrangement the housing maybe lpaited: .on-an intermediate transverse plane :for purposes of assemhly,as will be hereinafteridescribed.

The driven 'shaft is of special' `construction, having a .pair of diametricallyopposite radial l arms 39; and lll)l for-med integral 4with the yshattat a: suitable point intermediate theiends thereof. A shaft portion BZW-occurs `on the side ofthearm adjacent to the motor H). This receives a bushying 4i upon which 'ai composite :gear `unit 42 is mountedi and with :rela-tion'to which it mayireely rot-ate, Oneend of this unit provides a agear wheel-:A3 mesh with-the pinion A226; ThefODpO.- site Lenel of the unit provides a sun gear 44 in mesh-with 4.a series of-"planetn-gears '425i The planet gears are mounted `uponfpins 4.5,one of Which is shownias extendingthroughia bore in: radialarrns y:iii and 40. The opposite ends, of pins Miy are suppoctei by a .bearingplate 41..

The planet gears #Snare encircled :by and are innmesh withi an` internal ring gear 43.` 'Ehering gear 48 is carried upon a spider 49, which: is :termed a hub 50. Thishubis provided with bea-rings 5-| and, 5.2 through which the driven shaftextends. yAin oil-seal structure 53 iswforme'd around the driven sha-tt v32 adjacent to thebearing `5l This y*formsfan-:oil seal between the-driven shaft i2` and bore :Bief the hub.. An oileseafl :ring .sais secured complementary 'counterbres of the housing section I4 and I4 and engages the outer face of the ring gear 48. Thus, the compartment between the spider 49 and the housing web 28 will provide a grease-tight container within which the gears 26, 43, 44, 45, and 48 run. Attention is directed to the fact that by the use of oil rings 53, 55 and 34 the entire brake structure is sealed 011 from the gear case. This insures that the brake will remain dry While permitting the gears to be packed in grease.

It is intended that under normal circumstances the ring gear 48 will be held against rotation. This is accomplished by an overload brake 56 which acts as rotation restraining means. The brake comprises a plurality of dry brake plates 5'I splined onto keys 58 carried by the hub 50 of the web 49. Between these plates friction ldiscs 59 occur. These are splined to keys 60 carried by a sleeve 6| mounted within the lower housing section I 4. The sleeve is secured in position when the housing sections are bolted together. The housing section I4 carries a plurality of spring cavities 62 to receive brake springs 63. These bear against the brake plates and discs. The opposite side of the brake structure is held by an adjusting ring 64. This is externally threaded to engage the thread 65 within the sleeve 6I. A plurality of radial openings 66 are formed through the ring and are accessible through an opening B'I in the housing. This opening is normally closed by a plate 68 held by cap screws 69. The edge of the ring 64 is serrated to receive a lock tongue T6, which prevents rotation of the ring after it has been adjusted to impose a desired tension upon the brake elements and a desired compression of the springs 63.

In operation of the present invention the assembly of the structure will be first considered. The sleeve 6I may be placed in position with the lower brake disc 51 resting upon the springs 63, and with the adjusting ring 64 tightened into the sleeve 6I. This structure rests on the shoulder of the counterbore in the bolting ange 35 of the lower housing section I4', where it is held by screws 1I. I'he oil-seal ring 55 is seated within the counterbore of the bolting flange 31 of the housing section I4. The ring gear 48 with its spider 49 and hub 50 may then be introduced into the lower housing section I4 with the keys 58 engaging the splineways of the brake disc 51. The driven shaft 32 upon which is assembled the planetary gears 45 and their pins 46 may then be placed in position through the bearings 5I and 52 with the pinions 45 meshing with the ring gear 48. It will be understood that the shaft I9 with its gear I8 has been assembled Within the housing section I 4, and that when the housing section I4 is placed in assembled relation the housing section I4 with the pinion 26 in mesh with the gear 43 the entire structure will be assembled and can be held in its assembled position by the bolts 38. If desired the ring gear 48, the spider 49, and the hub 50 with the bearings 5I and 52 might be assembled as a unit with the driven shaft unit. In any event the drive will be concentric and the entisre structure will be a compact symmetrical uni In operation the motor I will drive the pinion I'I and will impart rotation to the gear I8. This in turn will drive the pinion 26 and the gear 43. The gear 43 is fixed to the gear 44 and will thus impart rotation to the planetary gears 45. Under normal conditions the planetary gears are in driving relation to the ring gear 48 which is held fixed by the brake 56. Thus a predetermined rotation of the driven shaft 32 will be imparted to the radial arms 39 and 40. A driving action will continue until an overload condition exists as determined by the setting of the brake ring 64, at which time the brake Will slip to allow rotation of the gear 48 and will thus prevent undue strain upon the 'driven shaft 32 and the parts which it drives.

It will thus be seen that the structure here disclosed is simple and compact in design, provides a desirable gear reduction, and a safety drive arrangement, which is particularly adapted as a driving unit for remotely controlled mechanism on airplanes and the like.

While we have shown the preferred form of our invention as now known to us, it will be understood that various changes may be made in combination, construction and arrangement of parts by those skilled in the art, without departing from the spirit of our invention as claimed.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

A driving unit, comprising a brake housing section and a gear housing section detachably connected along a plane normal to the longitudinal axis of the housing, a drive shaft rotatably mounted in the end of the gear housing section, a driven shaft rotatably mounted in the brake housing section and extending into the gear housing section, a sun gear freely rotatable upon the extending portion of the driven shaft, a gear train within the gear housing section imparting driving motion from the drive shaft to the sun gear, a spider carried on the driven shaft, planetary gears rotatably carried by the spider and in mesh with the sun gear, a ring gear disposed sub stantially at the parting line between the two.

housing sections, an oil seal ring disposed substantially at the parting line between the two housing sections and forming a seal between the circumference of the ring gear and the wall of the housing, a hub formed as part of the ring gear and extending longitudinally of the driven shaft Within the brake housing section and being rotatably supported upon said shaft, an oil seal ring disposed between said hub and the driven shaft, a friction disc brake disposed in the brake housing structure having elements engaging the hub of the ring gear, a liner removably mounted within the brake housing section and engaging the other elements of the brake structure, a pressure ring adjustably mounted within the liner and against which one side of the brake structure bears, and yieldable means mounted Within the brake housing section and bearing against the opposite side of the brake structure,

ROY E. THOMPSON. JOHN K. MORRIS.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Name Date Mosch Feb. 19, 1929 Mageoch Nov. 26, 1940 Heintz Feb. 3, 1942 Heintz Dec. l, 1942 Stein Sept. 5, 1933 Ragan Feb. 9, 1932 Christian May 31, 1932 Number 

